What are the chemical reactions involved in the production of SiO2 particles through vaporization, oxidation, and condensation?
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The production of SiO2 particles through vaporization, oxidation, and condensation involves various chemical reactions. In oxygen-rich circumstellar environments, SiO molecules react with OH radicals and H2O, affecting the efficiency of dust formation . Additionally, the reaction between SiO(g) and CO(g) on SiC particles at elevated temperatures leads to the formation of brown condensate, consisting of Si spheres embedded in a SiO2 matrix . Furthermore, a cost-efficient method for producing SiO2 particles involves depositing SiO2 onto core particles by decreasing the pH value of an aqueous reaction composition over time . Another method includes preparing a dispersion liquid of composite oxide particles with a specific molar ratio of MOx/SiO2 to obtain particles with an average diameter in a specific range .
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| The production of SiO2 particles involves vaporization of SiO(g) and CO(g), oxidation reactions, and condensation resulting in Si spheres embedded in a SiO2 matrix. | |
| Not addressed in the paper. | |
| The reactions involve SiO oxidation by OH and H2O, leading to SiO2 formation. Si2O2 reacts faster with OH than SiO, while SiO + H2O forms molecular complexes due to high activation energies. |
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